The Sam Rayburn Museum, located in Bonham,Texas, is one of the four divisions of the Dolph Briscoe Center for American History. It is the creation of the man who served as Speaker of the United States House of Representatives longer than any other person: Sam Taliaferro Rayburn (1882–1961). Known affectionately as "Mr. Sam" by his friends and colleagues, Rayburn established the museum in 1957 as a tribute to the people of his cherished Fannin County.

Sam Rayburn served as congressman during the administrations of eight presidents and participated in the passage of most of the significant legislation of the first half of the twentieth century. He became chairman of the powerful Committee on Interstate and Foreign Commerce in 1931 and House majority leader in 1937. Rayburn, as well as Vice President John Nance Garner, played a critical role in passing much of President Franklin D. Roosevelt's New Deal.

In 1941 Rayburn became Speaker of the House of Representatives, a position he held for sixteen years, longer than any other individual in U.S. history. Except for two brief periods when the Republican Party controlled the House (1947–1948 and 1953–1955), Rayburn continued to serve as Speaker until his death in 1961.

The Sam Rayburn Museum became a division of the Briscoe Center in 1991. The Museum is open to the public for visitation and tours. It contains exhibits on Sam Rayburn's life and career and features an exact replica of the office of the Speaker of the House of Representatives during Rayburn's tenure in that position. The Rayburn Museum also houses Rayburn's personal library and an extensive collection of books that relate to his career or to the people, issues, and events with which he dealt during his years of public service.

In 1949, Collier's Magazine awarded Sam Rayburn $10,000 for distinguished service to the nation. Rayburn used this award to establish an endowment that, with additional gifts, eventually grew large enough to support the construction and operation of a library and museum. Ground was broken for the Sam Rayburn Museum in December 1955 and the Sam Rayburn Museum was dedicated in 1957. From 1957 to 1990 the Rayburn Museum was operated under the auspices of the Rayburn Foundation. On January 1, 1991, ownership of the Sam Rayburn Museum was transferred to the University of Texas at Austin and was established as a division of the Briscoe Center for American History.